In the existing multi-carrier communication system architecture, a signal is sent out from a transmitter after being dealt with mapping, spreading, serial-parallel transforming, inverse discrete Fourier transforming, digital to analog converting, power amplifying and etc; then, the signal is received by a receiver and restored after being dealt with analog to digital converting, discrete Fourier transforming, parallel-serial transforming, de-spreading, de-mapping and etc.
However, the signal in a multi-carrier communication system is obtained by superimposing a plurality of sub-carrier channel signals, the maximum instantaneous power of the signal may vary greatly with a average power, that will produce a high Peak to Average Power Ratio (PAPR). A higher PAPR requires the power amplifier of the transmitter to have a larger linear dynamic range for avoiding signal distortion.